There's lots of talk about three families getting together.
How many families are involved in the prospective 19th event?
I would be wary to be honest. I think it's silly to expect both to happen. Maybe your brother-in-law's family are simply less careful. There will be lots of issues like this over Christmas I think.
Good luck.
What "back then" inconvenience would annoy today's youngsters?
Inadequate kitchen equipment in holiday accommodation.
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